diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py
index 4ea0c3fb06..41d625186c 100644
--- a/django/db/models/fields/related.py
+++ b/django/db/models/fields/related.py
@@ -351,7 +351,7 @@ def create_many_related_manager(superclass):
             self.target_col_name = target_col_name
             self._pk_val = self.instance._get_pk_val()
             if self._pk_val is None:
-                raise ValueError("%r instance needs to have a primary key value before a many-to-many relationship can be used." % model)
+                raise ValueError("%r instance needs to have a primary key value before a many-to-many relationship can be used." % instance.__class__.__name__)
 
         def get_query_set(self):
             return superclass.get_query_set(self).filter(**(self.core_filters))
diff --git a/tests/modeltests/many_to_many/models.py b/tests/modeltests/many_to_many/models.py
index e09fd825f8..c2ab2897b6 100644
--- a/tests/modeltests/many_to_many/models.py
+++ b/tests/modeltests/many_to_many/models.py
@@ -39,6 +39,14 @@ __test__ = {'API_TESTS':"""
 
 # Create an Article.
 >>> a1 = Article(id=None, headline='Django lets you build Web apps easily')
+
+# You can't associate it with a Publication until it's been saved.
+>>> a1.publications.add(p1)
+Traceback (most recent call last):
+...
+ValueError: 'Article' instance needs to have a primary key value before a many-to-many relationship can be used.
+
+# Save it!
 >>> a1.save()
 
 # Associate the Article with a Publication.